Pituitary adenoma presenting as sinonasal tumor: pitfalls in diagnosis

Top 10 Nested Pattern Head and Neck Lesions to Notice

BACKGROUND

Nested is defined as "cellular clusters arranged in small groupings with intervening vascular or stromal networks, lacking lumens or glandular formation." Using this definition, multiple neoplastic and non-neoplastic lesions of the head and neck come into the differential. We have broadly organized the differential diagnosis of "nested" tumors into entities with neuroendocrine differentiation, squamous differentiation, thyroid follicular cell differentiation, and other lesions.

METHODS

Review.

RESULTS

Many different entities have a nested appearance and the morphologic, immunohistochemical, clinical, and radiographic features contribute to the differential diagnosis. The different tumors covered in this review include neuroendocrine neoplasms, paraganglioma, middle ear neuroendocrine tumor (formerly known as middle ear adenoma), medullary thyroid carcinoma, poorly differentiated thyroid carcinoma, olfactory neuroblastoma, ectopic pituitary neuroendocrine tumor, hyalinizing trabecular tumor, solid subtype of papillary thyroid carcinoma, solid cell nests/C-cell hyperplasia, necrotizing sialometaplasia, and meningioma.

CONCLUSION

In this review, we discuss the morphologic and immunohistochemical features of the covered entities as a guide to differential diagnosis when nested-patterned head and neck lesions are encountered.

Clinical and radiological presentation of parasellar ectopic pituitary adenomas: case series and systematic review of the literature

PURPOSE

Parasellar ectopic pituitary adenomas (pEPAs) are extremely rare tumors located out of the sella turcica. PEPAs are heterogeneous entities in terms of anatomical localization and secretion of anterior pituitary hormones.

METHODS

Multicenter retrospective study. Clinical charts' consultation of patients diagnosed with parasellar lesions, to identify all subjects fulfilling the diagnostic criteria of parasellar EPAs. Systematic review of the literature focused on the medical management of prolactin-secreting pEPAs and on the prevalence of radiological bone invasion in pEPAs.

RESULTS

We identified four cases of pEPAs: (1) 54-year-old female with a prolactin-secreting suprasellar EPA successfully treated with cabergoline; (2) 74-year-old male with a non-functioning EPA of the sphenoidal sinus treated with endoscopic transsphenoidal surgery; (3) 75-year-old female with a giant lesion of the skull base (maximum diameter 7.2 cm) diagnosed as a non-functioning EPA after biopsy; (4) 49-year-old male with a silent corticotroph EPA of the sphenoidal sinus and clivus. Three out of four cases had radiological evidence of invasion of the surrounding bone structures. A systematic review of the literature highlighted that medical therapy can be effective in prolactin-secreting pEPAs. Overall, we found mention of local invasiveness in 65/147 cases (44.2%), confirmed by radiological signs of bone invasion/erosion.

CONCLUSION

Our experience confirms the heterogeneity of pEPAs in terms of clinical and radiological presentation, as well as hormone secretion. PEPAs show a high frequency of radiological bone invasion, though similar to that of sellar pituitary adenomas. Although extremely rare, pEPAs need to be considered in the differential diagnosis of parasellar lesions.

Ectopic pituitary adenomas: clinical features, diagnostic challenges and management

PURPOSE

Ectopic pituitary adenomas (EPAs) are extremely rare pituitary adenomas located outside the sella turcica without any connection with intrasellar components. This study aims to review all the reported cases to date and describe the clinical characteristics of EPAs.

METHODS

In a retrospective chart review, 14 patients were identified with EPAs in our hospital. A literature review was performed, and 166 cases in the literature met the criteria. Clinical data were analyzed.

RESULTS

Of 180 patients with EPAs, the mean age at diagnosis was 45.4 years, and 66.5% of the patients were females. EPAs were mainly located in the sphenoid sinus (34.4%) and suprasellar region (25.6%), followed by the clivus (15.6%), cavernous sinus (13.3%) and nasopharynx (5.6%). Adrenocorticotropic hormone (ACTH)-secreting (38.9%) and nonfunctioning (27.2%) adenomas were predominant. Patients with suprasellar EPAs were more likely to present menstrual disorders and visual changes, while patients with clival EPAs were more likely to suffer from headaches. EPAs in the cavernous sinus and suprasellar space were more likely to be initially misdiagnosed as a suspicious intrasellar mass on imaging examination. The complete tumor resection rates for EPAs in the sphenoid sinus, suprasellar region, clivus, cavernous sinus and nasopharynx were 72.3%, 88.6%, 45.0%, 73.3% and 88.9%, respectively.

CONCLUSIONS

EPA clinical characteristics varied across different tumor locations and hormone-secreting types. In addition to comprehensive hormone evaluation and careful review of imaging data, nuclear medicine and surgical biopsy should also be considered when facing differential difficulty. EPA management should be individualized.

Pituitary Adenomas Presenting as Sinonasal or Nasopharyngeal Masses: A Case Series Illustrating Potential Diagnostic Pitfalls

We present a series of nonectopic pituitary adenomas presenting as polypoid sinonasal or nasopharyngeal masses. Thirteen cases diagnosed by biopsies from the nasal cavity, sinuses, or nasopharynx were identified from a series of 1288 surgical pituitary specimens. The patients included 5 men and 8 women ranging from 29 to 69 years of age. The presentations included nasal obstruction (4 cases), headaches (3), visual defects (2), recurrent nose bleeds (1), rhinorrhea (1), sepsis (1), fatigue (1), and hyperthyroidism (1). All patients had large tumors involving the sella and extending inferiorly to involve the sphenoid sinus in 10 cases, ethmoid in 8, nasopharynx in 3, nasal cavity in 6, maxillary and frontal sinuses in 1 case each. In 3 patients, the biopsy was from the nasopharynx, in 4 from the nasal cavity, in 4 from the sphenoid sinus, and in 2 from the ethmoid sinus. The correct diagnosis of pituitary adenoma was initially made in 10 cases. In 3 cases the initial diagnosis was incorrect; 2 tumors were classified as olfactory neuroblastoma, one of those was reclassified as neuroendocrine carcinoma, and 1 case was initially diagnosed as neuroendocrine carcinoma with aberrant adrenocorticotrophic hormone expression. Clinical follow-up (2 to 25 y) and treatment information was available in 10 cases. All 10 patients were alive, either free of disease (4 cases) or with disease (6 cases). In 2 cases, the wrong diagnoses led to incorrect treatment with significant morbidity. These cases illustrate that pituitary adenomas can invade nasopharynx and sinonasal cavities and when they do, they present a possible diagnostic pitfall with potentially serious consequences. We demonstrate the need to always consider this entity when encountering a nasopharyngeal or sinonasal tumor with neuroendocrine features.

Update From The 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Nasopharynx

The current WHO classification system for tumors of the head and neck has made few changes from the previous edition with regards to tumors of the nasopharynx. The classification system is discussed here with particular attention to nasopharyngeal carcinoma, nasopharyngeal papillary adenocarcinoma, salivary gland anlage tumor, hairy polyp, juvenile angiofibroma, and other tumors.

Giant Prolactinoma Presenting As a Base of Skull Tumor With Nasopharyngeal Extension: A Potential Diagnostic Pitfall in Neuroendocrine Lesions of the Base of Skull

Pituitary adenomas presenting in uncommon anatomical locations are commonly misdiagnosed. Dramatic clinical presentation with hemorrhage and infarction, along with a lack of endocrine symptoms may further confound the diagnosis in some patients as illustrated in one of our two previously reported cases of non-small cell neuroendocrine carcinoma of the sinonasal tract and nasopharynx. This report presents the clinical progress of case number 2, which has a revised diagnosis of giant lactotroph pituitary adenoma. Common clinical, radiological and pathological pitfalls in diagnosis of neuroendocrine neoplasms of the sinonasal tract and base of skull are discussed.

Sinonasal Small Round Blue Cell Tumors: An Immunohistochemical Approach

Although clinical history and morphologic appearance should be the initial considerations when evaluating small round blue cell tumors of the sinonasal tract, the final diagnosis often hinges on immunohistochemical findings. Unfortunately, interpretation of stains in these tumors is fraught with numerous pitfalls and limitations. This article presents an approach to sinonasal small round blue cell tumors based on four common immunohistochemical patterns: cytokeratin positivity, squamous marker positivity, neuroendocrine marker positivity, and cytokeratin negativity.

Nasal Cavity and Paranasal Sinuses

The nasal cavity and paranasal sinuses occupy the top of the upper respiratory tract and form pneumatic spaces connected with the atmosphere. They are located immediately beneath the base of the cranium, where crucial vital structures are harbored. From this region, very much exposed to airborne agents, arise some of the more complex and rare benign and malignant lesions seen in humans, whose difficulties in interpretation make this remarkable territory one of the most challenging in the practice of surgical pathology.

Contents of this chapter cover inflammations and infections, polyps and pseudotumors, fungal and midfacial destructive granulomatous lesions, as well as benign, borderline, and malignant neoplasms. Among the neoplasms, emphasis is made on those entities characteristic or even unique for the sinonasal region, such as Schneiderian papillomas, glomangiopericytoma, intestinal- and non-intestinal-type adenocarcinomas, olfactory neuroblastoma, nasal-type NK-/T-cell lymphoma, and teratocarcinosarcoma. Moreover, recently recognized entities involving this territory, i.e., HPV-related non-keratinizing carcinoma, NUT carcinoma, and SMARCB1-deficient basaloid carcinoma, are also discussed in the light of their specific molecular findings. Furthermore, the text is accompanied by numerous classical and recent references, several tables, and 100 illustrations.

Thyroid-stimulating hormone-secreting ectopic pituitary adenoma of the nasopharynx

Thyroid-stimulating hormone-secreting ectopic pituitary adenoma of the nasopharynx is highly unusual, with only three reported cases in the world literature. We describe the clinical presentation and radiologic findings in one patient with such rare lesions. A 46-year-old male with typical symptoms of Grave's disease was found to have a mass on magnetic resonance imaging. An otolaryngologic examination revealed a nasopharyngeal mass lesion, which was endoscopically resected. The results of immunohistochemical staining for thyroid-stimulating hormone were positive. After the resection, the patient's TSH was within normal limits. The clinical significance of the case and a brief literature review are presented.

A whiff of trouble: tumours of the nasal cavity and their mimics

A range of disease entities can affect the nasal cavity, often presenting with variable and non-specific symptoms. There is considerable overlap between the clinical and radiological features of neoplastic and non-neoplastic entities. The nasal cavity is often included in routine imaging of the brain, middle ear, skull base, and paranasal sinuses and should be included as a critical review area. The definitive diagnosis is in most cases confirmed by histopathological analysis. However, this review highlights the role of imaging in identifying nasal cavity disease, eliciting features of aggressive or indolent behaviour, and helping to narrow the differential diagnosis, thus facilitating a systematic approach when reviewing the nasal cavity.

An interesting case of pituitary adenoma presenting as an invasive nasopharyngeal tumor

Pituitary masses usually present as sellar masses with suprasellar or parasellar extension. However, in unusual cases pituitary tumors especially macroprolactinomas and nonfunctional adenomas can present with intranasal extension which can be misdiagnosed as nasal polyp or a primary invasive nasopharyngeal malignant tumor. The otolaryngologists should be familiar with this rare presentation of pituitary masses. Measurement of prolactin (PRL) is essential in cases of recalcitrant nasal polyps or rhinorrhea as it may change the management in such cases. Here we describe case of a patient with an invasive pituitary adenoma who had presented in the otorhinolaryngology department with a nasal obstruction and epistaxis. We have also reviewed 30 cases of pituitary adenoma with nasopharyngeal invasion published in past.

Epistaxis as first clinical presentation in a child with giant prolactinoma: Case report and review of literature

Pituitary tumour have a wide way of presentation. Epistaxis due to pituitary adenoma has been rarely reported. There is no report of bleeding from nose as clinical first presentation in a child. We report the first case in literature where a child had epistaxis for eight months before deterioration of vision. He was found to be having a invasive prolactinoma with normal prolactin levels.

Ectopic sphenoid sinus pituitary adenoma (ESSPA) with normal anterior pituitary gland: a clinicopathologic and immunophenotypic study of 32 cases with a comprehensive review of the english literature

Ectopic sphenoid sinus pituitary adenoma (ESSPA) may arise from a remnant of Rathke's pouch. These tumors are frequently misdiagnosed as other neuroendocrine or epithelial neoplasms which may develop in this site (olfactory neuroblastoma, neuroendocrine carcinoma, sinonasal undifferentiated carcinoma, paraganglioma, melanoma). Thirty-two patients with ESSPA identified in patients with normal pituitary glands (intact sella turcica) were retrospectively retrieved from the consultation files of the authors' institutions. Clinical records were reviewed with follow-up obtained. An immunohistochemical panel was performed on available material. Sixteen males and 16 females, aged 2-84 years (mean, 57.1 years), presented with chronic sinusitis, headache, obstructive symptoms, and visual field defects, although several were asymptomatic (n = 6). By definition, the tumors were centered within the sphenoid sinus and demonstrated, by imaging studies or intraoperative examination, a normal sella turcica without a concurrent pituitary adenoma. A subset of tumors showed extension into the nasal cavity (n = 5) or nasopharynx (n = 9). Mean tumor size was 3.4 cm. The majority of tumors were beneath an intact respiratory epithelium (n = 22), arranged in many different patterns (solid, packets, organoid, pseudorosette-rosette, pseudopapillary, single file, glandular, trabecular, insular). Bone involvement was frequently seen (n = 21). Secretions were present (n = 16). Necrosis was noted in 8 tumors. The tumors showed a variable cellularity, with polygonal, plasmacytoid, granular, and oncocytic tumor cells. Severe pleomorphism was uncommon (n = 5). A delicate, salt-and-pepper chromatin distribution was seen. In addition, there were intranuclear cytoplasmic inclusions (n = 25) and multinucleated tumor cells (n = 18). Mitotic figures were infrequent, with a mean of 1 per 10 HPFs and a <1% proliferation index (Ki-67). There was a vascularized to sclerotic or calcified stroma. Immunohistochemistry highlighted the endocrine nature of the tumors, with synaptophysin (97%), CD56 (91%), NSE (76%) and chromogranin (71%); while pan-cytokeratin was positive in 79%, frequently with a dot-like Golgi accentuation (50%). Reactivity with pituitary hormones included 48% reactive for 2 or more hormones (plurihormonal), and 33% reactive for a single hormone, with prolactin seen most frequently (59%); 19% of cases were non-reactive. The principle differential diagnosis includes olfactory neuroblastoma, neuroendocrine carcinoma, melanoma, and meningioma. All patients were treated with surgery. No patients died from disease, although one patient died with persistent disease (0.8 months). Surgery is curative in the majority of cases, although recurrence/persistence was seen in 4 patients (13.8%). In conclusion, ESSPAs are rare, affecting middle aged patients with non-specific symptoms, showing characteristic light microscopy and immunohistochemical features of their intrasellar counterparts. When encountering a tumor within the sphenoid sinus, ectopic pituitary adenoma must be considered, and pertinent imaging, clinical, and immunohistochemical evaluation undertaken to exclude tumors within the differential diagnosis. This will result in accurate classification, helping to prevent the potentially untoward side effects or complications of incorrect therapy.

Sinonasal inverted papilloma mimicking a pituitary macroadenoma

We report the rare entity of an inverted papilloma arising from the sphenoid sinus that we expected to be a pituitary tumour on the basis of history, examination and pre-operative investigations, especially MRI appearance. Inverted sinonasal papilloma should be considered in the differential diagnosis of pituitary macroadenoma invading the sphenoid sinus.

Ectopic neural and neuroendocrine neoplasms

Although neural and neuroendocrine tissues are distributed virtually ubiquitously throughout the body, the occurrence of selected neoplasms related to those lineages is extremely uncommon in some topographic sites. This review considers the clinicopathologic characteristics of heterotopic pituitary adenomas; neuroendocrine carcinomas in non-organ-based locations; ectopic (extraneuraxial) meningiomas and gliomas; visceral neuroblastic neoplasms and primitive neuroectodermal tumors; and paragangliomas arising outside the sympathoadrenal neural network. Practical approaches to differential diagnosis are emphasized.

Ectopic Growth Hormone-Releasing Adenoma in the Cavernous Sinus-Case Report-

A 55-year-old woman presented a rare ectopic pituitary adenoma in the right cavernous sinus manifesting as acromegaly. The tumor was removed via transsphenoidal approach. Intraoperative observation showed the adenoma was located entirely within the right cavernous sinus, and separated from the normal pituitary gland by the medial wall of the cavernous sinus. There was no communication between the tumor and the pituitary. Histological examination showed a growth hormone-releasing adenoma. Including our case, only eight of 86 reported ectopic adenomas have occurred in the cavernous sinus. Such ectopic presentation may be responsible for failed transsphenoidal surgery for endocrinologically active tumors.

Misdiagnosis of olfactory neuroblastoma

OBJECT

Olfactory neuroblastoma (ON) is a rare neoplasm arising from the olfactory epithelium and found in the upper nasal cavity. The authors studied the frequency with which ON is misdiagnosed with other tumors of the paranasal sinuses such as neuroendocrine carcinoma (NEC), pituitary adenoma, melanoma, lymphoma, and sinonasal undifferentiated carcinoma (SNUC). Based on the belief that misdiagnosis commonly occurs, they emphasized the importance of establishing the correct diagnosis, because the treatment regimens and prognosis of these tumor types are often significantly different.

METHODS

Twelve consecutive patients in whom ON was diagnosed were referred to the Department of Neurosurgery at the M. D. Anderson Cancer Center between January 1998 and March 2000. Demographic data were collected, physical findings and mode of treatments were documented, and neuroimaging studies were assessed. Pathologists at the authors' institute reviewed the histological specimens. Only in two of 12 patients was the diagnosis of ON confirmed. Lesions in 10 patients were misdiagnosed; there were two cases of melanoma, three cases of NEC, three cases of pituitary adenoma, and two cases of SNUC. Eight of 10 patients in whom lesions were misdiagnosed required significant alteration in the initially proposed treatment plan.

CONCLUSIONS

Neurosurgeons should be acutely aware of the variety of neoplasms that occur in the paranasal region. The correct diagnosis should be ensured before initiating treatment to provide the optimum therapy and spare the patients from needless and potentially toxic treatment.

Suprasellar adrenocorticotropic hormone-secreting ectopic pituitary adenoma: case report and literature Review

OBJECTIVE AND IMPORTANCE

Functional ectopic pituitary adenomas are rare and can be misdiagnosed as extensions of pituitary adenomas when they are located in the vicinity of the normal gland. In this report, we present a case of an ectopic adrenocorticotropic hormone-secreting suprasellar pituitary adenoma that caused Cushing's disease. A literature review of previously reported ectopic pituitary adenomas is included to illustrate the diverse clinical manifestations of this disease entity.

CLINICAL PRESENTATION

An 11-year-old boy was noted to have hirsutism, a buffalo hump, and unexplained weight gain consistent with Cushing's syndrome. Laboratory investigations revealed that the boy had elevated adrenocorticotropic hormone and serum cortisol levels unsuppressed by dexamethasone. Magnetic resonance imaging scans were suggestive of a pituitary adenoma with suprasellar extension.

INTERVENTION

The initial transsphenoidal approach failed to achieve complete surgical resection. A repeat operation in which the pterional approach was used revealed a suprasellar pituitary adenoma without association with intrasellar contents. The patient's cushingoid symptoms improved significantly 3 months after surgery.

CONCLUSION

Ectopic pituitary adenomas should be considered in the differential diagnosis for all patients with Cushing's syndrome. Furthermore, surgical approaches should be chosen carefully once the diagnosis of ectopic pituitary adenoma is made.

Pathology of skull base tumors

The multidisciplinary requirements of skull base surgery have evolved over the last 25 years. The heterogeneity of tissue types in the cranium base gives rise to a diverse group of benign and malignant neoplasms with vastly different prognoses. This article reviews the distinct clinicopathologic features of some of the unique and problematic neoplasms of this region.

Pituitary adenomas with infra-sellar extension into the nasopharynx

Three cases of pituitary adenomas with infra-sellar extension into the nasopharynx and the nasal cavities are reported. The clinical signs were epistaxis, nasal obstruction, painful sinuses and purulent rhinorrhoea. The initial diagnostic hypothesis was that of a carcinoma of the nasopharynx or the sinuses in all three cases. The diagnosis was made by histological examination and measurement of plasma hormone levels. These cases highlight the difficulty in the diagnosis of such tumours due to their misleading clinical, radiological and histological features.